Abstract：
BACKGROUND: Arrhythmogenic left ventricular cardiomyopathy (ALVC) is characterized by fibrofatty myocardial replacement demonstrated on cardiac magnetic resonance by late gadolinium enhancement (LGE) mainly involving the subepicardium. The aims of this study were to describe the layer-specific strain (LSS) echocardiography phenotype of ALVC and to compare it with LGE features.
METHODS: All consecutive ALVC pathogenic genetic variant carriers and noncarrier relatives were separated into four prespecified groups (overt ALVC [group 1], isolated LGE [group 2], pathogenic genetic variant carrier without ALVC phenotype [group 3], and no genetic variant carrier [group 4]) and studied accordingly using cardiac magnetic resonance and LSS echocardiography.
RESULTS: Eighty-five individuals were included. Endocardial global longitudinal strain (GLS)-epicardial GLS (GLSepi) gradient was altered predominantly in group 1, illustrating transmural strain alteration in overt ALVC (3.8 ± 1.1 in group 1, 4.3 ± 2.2 in group 2, 5.2 ± 1.2 in group 3, and 5.4 ± 1.6 in group 4; P = .0017), whereas GLSepi was impaired predominantly in group 2 (endocardial GLS and GLSepi were 15.0 ± 4.1% and 11.2 ± 3.3%, respectively, in group 1; 20.5 ± 2.8% and 16.2 ± 5.5% in group 2; 23.4 ± 3.3% and 18.2 ± 2.7% in group 3; and 24.6 ± 2.8% and 19.2 ± 1.9% in group 4; P < .0001 for all). GLSepi was able to detect subepicardial LGE in genetic variant carriers without overt ALVC with an area under curve of 0.84 (95% CI, 0.73-0.95). However, segmental epicardial and endocardial strain behaved similarly and showed comparable diagnostic values for segmental LGE detection (areas under the curve, 0.72; [95% CI, 0.69-0.76] and 0.73 [95% CI, 0.70-0.76], respectively, P = .40).
CONCLUSIONS: LSS alteration in ALVC progresses from the epicardium to the endocardium along with disease severity. Irrespective of LSS analysis, which did not provide incremental diagnostic value for the detection and localization of LGE, strain echocardiography was shown to be a potential surrogate marker of LGE, including in apparently healthy individuals with isolated LV fibrosis.
METHODS: All consecutive ALVC pathogenic genetic variant carriers and noncarrier relatives were separated into four prespecified groups (overt ALVC [group 1], isolated LGE [group 2], pathogenic genetic variant carrier without ALVC phenotype [group 3], and no genetic variant carrier [group 4]) and studied accordingly using cardiac magnetic resonance and LSS echocardiography.
RESULTS: Eighty-five individuals were included. Endocardial global longitudinal strain (GLS)-epicardial GLS (GLSepi) gradient was altered predominantly in group 1, illustrating transmural strain alteration in overt ALVC (3.8 ± 1.1 in group 1, 4.3 ± 2.2 in group 2, 5.2 ± 1.2 in group 3, and 5.4 ± 1.6 in group 4; P = .0017), whereas GLSepi was impaired predominantly in group 2 (endocardial GLS and GLSepi were 15.0 ± 4.1% and 11.2 ± 3.3%, respectively, in group 1; 20.5 ± 2.8% and 16.2 ± 5.5% in group 2; 23.4 ± 3.3% and 18.2 ± 2.7% in group 3; and 24.6 ± 2.8% and 19.2 ± 1.9% in group 4; P < .0001 for all). GLSepi was able to detect subepicardial LGE in genetic variant carriers without overt ALVC with an area under curve of 0.84 (95% CI, 0.73-0.95). However, segmental epicardial and endocardial strain behaved similarly and showed comparable diagnostic values for segmental LGE detection (areas under the curve, 0.72; [95% CI, 0.69-0.76] and 0.73 [95% CI, 0.70-0.76], respectively, P = .40).
CONCLUSIONS: LSS alteration in ALVC progresses from the epicardium to the endocardium along with disease severity. Irrespective of LSS analysis, which did not provide incremental diagnostic value for the detection and localization of LGE, strain echocardiography was shown to be a potential surrogate marker of LGE, including in apparently healthy individuals with isolated LV fibrosis.
摘要：
背景：致心律失常性左心室心肌病（ALVC）的特征是在心脏磁共振（CMR）上通过晚期钆增强（LGE）证实的纤维脂肪心肌替代，主要涉及心膜下。该研究旨在描述ALVC的层特异性应变（LSS）超声心动图表型，并将其与LGE特征进行比较。
方法：将所有连续的ALVC致病遗传变异携带者和非携带者亲属分为四个预先指定的组（明显的ALVC（第1组），孤立的LGE（第2组），无ALVC表型的致病性遗传变异携带者(第3组)，无遗传变异携带者（第4组）），并通过CMR和LSS超声心动图进行了相应的探索。
结果：纳入85人。心内膜整体纵向应变（GLS）（GLSendo）-心外膜GLS（GLSepi）梯度在第1组中主要改变，说明明显ALVC的透壁应变改变（第1组3.8±1.1，第2组4.3±2.2，第3组5.2±1.2，第4组5.4±1.6，p=0.0017），而GLSepi在第2组中主要受损(GLSendo，GLSepi=15.0±4.1%，第一组分别为11.2±3.3%，20.5±2.8%，第2组16.2±5.5％，23.4±3.3％，第3组18.2±2.7%，24.6±2.8%，第4组中19.2±1.9%，所有p<0.0001)。GLSepi能够在没有明显ALVC的遗传变异携带者中检测到心外膜下LGE，曲线下面积（AUC）为0.84（0.73;0.95）。然而,节段性心外膜和心内膜应变表现相似，并显示节段性LGE检测的相当诊断值(AUC0.72(CI0.69-0.76)和0.73(CI0.70-0.76)，p=0.4)。
结论：ALVC的LSS改变随着疾病严重程度从心外膜进展到心内膜。不考虑LSS分析，没有为LGE的检测和定位提供增量诊断价值，应变超声心动图被证明是LGE的潜在替代标记，包括患有孤立性LV纤维化的明显健康个体。
方法：将所有连续的ALVC致病遗传变异携带者和非携带者亲属分为四个预先指定的组（明显的ALVC（第1组），孤立的LGE（第2组），无ALVC表型的致病性遗传变异携带者(第3组)，无遗传变异携带者（第4组）），并通过CMR和LSS超声心动图进行了相应的探索。
结果：纳入85人。心内膜整体纵向应变（GLS）（GLSendo）-心外膜GLS（GLSepi）梯度在第1组中主要改变，说明明显ALVC的透壁应变改变（第1组3.8±1.1，第2组4.3±2.2，第3组5.2±1.2，第4组5.4±1.6，p=0.0017），而GLSepi在第2组中主要受损(GLSendo，GLSepi=15.0±4.1%，第一组分别为11.2±3.3%，20.5±2.8%，第2组16.2±5.5％，23.4±3.3％，第3组18.2±2.7%，24.6±2.8%，第4组中19.2±1.9%，所有p<0.0001)。GLSepi能够在没有明显ALVC的遗传变异携带者中检测到心外膜下LGE，曲线下面积（AUC）为0.84（0.73;0.95）。然而,节段性心外膜和心内膜应变表现相似，并显示节段性LGE检测的相当诊断值(AUC0.72(CI0.69-0.76)和0.73(CI0.70-0.76)，p=0.4)。
结论：ALVC的LSS改变随着疾病严重程度从心外膜进展到心内膜。不考虑LSS分析，没有为LGE的检测和定位提供增量诊断价值，应变超声心动图被证明是LGE的潜在替代标记，包括患有孤立性LV纤维化的明显健康个体。
